The problem with many wheels is that they lack multi-directional movement. For example a castor wheel of a shopping trolley, although technically able to move in many different directions is frequently difficult to move in the direction the person pushing the trolley, wishes to move.
Much of the problem with the above castor wheel is associated with pushing of the trolley rather than pulling of the trolley. Because the castor wheel is actually only able to rotate in one plane, its multi-directional movement depends upon rotation of the shaft to which it is connected.
In a similar fashion articulated joints frequently are limited to movement in one plane in a similar fashion to a typical hinge.